CN1072393C - Ball Array Integrated Circuit Packaging Method - Google Patents

Abstract

A ball array type integrated circuit package method is to form the conducting wire and metal salient point which are protruded out of the upper surface on the thin copper sheet by dry film coating and electroplating, then to remove the thin copper sheet at the bottom layer after the steps of chip implanting, wire connecting and glue pouring are carried out on the surface of the conducting wire and metal salient point in sequence, so as to expose the conducting wire circuit and metal salient point, then to remove the conducting wire between the adjacent chips by green paint coating, ball kicking welding and etching, so as to separate the chips and form the mutually independent ball array type integrated circuit package.

Description

Ball Array Integrated Circuit Packaging Method

The invention relates to a packaging method of a ball array integrated circuit, which is a packaging method of a ball array (BGA) integrated circuit without using a substrate, so as to make the outer packaging more compact.

In order to meet the needs of different occasions, the outer packaging of integrated circuits today has a variety of different packaging forms, such as DIP, PGA, BGA, TAB... and other types, and BGA (BALL GRID ARRAY) integrated As far as the outer packaging of the circuit is concerned, it is formed on the bottom surface of the integrated circuit outer packaging with a large number of solder ball joints arranged vertically and horizontally, and is heated and welded to the corresponding contacts of the circuit board. Under the support and the medium used as the solder ball and the chip, the circuit board is generally required to be used as the "support substrate". In the package with the substrate, the thickness of the outer package will increase. When used on strict notebook or sub-notebook computers, there is a problem of taking up too much space, so it is necessary to improve it.

The main purpose of the present invention is to provide a substrate-less ball array integrated circuit packaging method, so as to omit the substrate and make the packaging more light, thinner and shorter.

To achieve the above object, the present invention takes the following technical solutions:

The ball array integrated circuit packaging method of the present invention comprises the following steps:

a. Apply dry film and electroplating on the copper sheet to form a circuit;

b. Implanting the circuit into a chip;

c. connecting the chip and the circuit;

d. potting glue to cover the wafer;

e. Etching and removing the copper sheet to expose the circuit;

f. Implant solder balls corresponding to the contact positions of the lines;

g. Etching removes redundant lines between adjacent chips to form individual chip packages.

The method for packaging the ball array integrated circuit is characterized in that it further includes the step of coating green paint. After the step of implanting solder balls is completed, the step of coating green paint is performed to protect the circuit part.

The ball array integrated circuit packaging method is characterized in that: the circuit formed by the electroplating is in the form of protruding.

The ball array integrated circuit packaging method is characterized in that it also includes a step of coating green paint, and after the step of etching to remove redundant circuits, the step of coating green paint is performed.

Compared with the traditional packaging method, the ball array integrated circuit packaging method of the present invention has the following effects:

The packaging method of the present invention only has lines and electroplating bumps 30, which can make the outer package lighter and smaller, and actively help to reduce the thickness of the package, so it is a novel and progressive ball array integrated circuit package. method.

The specific structural features and purposes of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Brief description of the drawings:

1A-G are schematic diagrams of the method steps of the present invention.

In the present invention, the final product can be packaged without a substrate. The packaging method is roughly as shown in FIGS. 1A-G . The position covered by the dry film 20 is electroplated for forming electroplating bumps 30 protruding upward as shown in FIG. This step is to attach several chips 40 to the surface of the thin copper sheet 10 with electroplating lines by bonding or bonding at appropriate intervals, and then, through the wiring step as shown in Figure 1C, each pin of each chip 40 is welded Gold wires 41 are used to connect to corresponding electroplating bumps 30 positions. Next, the step of pouring glue as shown in FIG. Intrusion of air or improper irradiation, after the protective glue 50 hardens, can be carried out as shown in Figure 1E, etch to remove the aforementioned thin copper sheet 10, so that the aforementioned electroplating bumps 30 and electroplating lines are exposed, and then, as shown in Figure 1F As shown, green paint (anti-oxidation film) is coated on the exposed electroplating circuit positions that do not need to be implanted with solder balls, and then the exposed electroplating bumps 30 are implanted with solder balls 70, so that the corresponding wafers 40 The bottom surface forms an array of solder ball contacts (that is, forms a BGA integrated circuit package). Since there are still electroplating lines 11 connected to each other between adjacent chips 40 in FIG. 1F, that is, in the final step, as shown in FIG. 1G , performing an etching step again to etch and remove the aforementioned electroplating circuit 11 and then performing a step of coating green paint protection, so that adjacent chips are completely separated into independent packaging forms, thus completing the packaging process.

For the sake of convenience of description, the above-mentioned packaging method is described as only two chips are attached. In fact, this packaging method is to carry out simultaneous packaging and molding of several chips at the same time, which is specially stated.

During the aforementioned packaging operation, the thin copper sheet 10 is directly used as a support in the middle process. After the glue is poured, the protective glue 50 can be used to provide the proper support strength. Therefore, in the subsequent steps, it can be The thin copper sheet 10 is directly etched away to form a BGA integrated circuit package without a support substrate at all, which is the originality and ingenuity of the present invention. Look, it is only formed with lines and plating bumps 30. Compared with the traditional packaging method, the outer packaging can be made lighter and smaller, and it actively helps to reduce the thickness of the packaging. Therefore, it is a novel and progressive packaging method. Ball array integrated circuit packaging method.

Claims (4)

1. A ball array integrated circuit packaging method, characterized in that: comprising the following steps: a. Apply dry film and electroplating on the copper sheet to form a circuit; b. Implanting the circuit into a chip; c. connecting the chip and the circuit; d. potting glue to cover the wafer; e. Etching and removing the copper sheet to expose the circuit; f. Implant solder balls corresponding to the contact positions of the lines; g. Etching removes redundant lines between adjacent chips to form individual chip packages. 2. The ball array integrated circuit packaging method according to claim 1, further comprising the step of coating green paint, after the step of implanting solder balls is completed, the step of coating green paint is carried out, To protect the line part. 3. The ball array integrated circuit packaging method according to claim 1, characterized in that: the lines formed by the electroplating are protruding. 4. The ball array integrated circuit packaging method according to claim 1 or 2, characterized in that: it also includes a step of coating green paint, after the step of etching to remove redundant circuits, then coating green paint A step of.